In a detailed comparison of matched samples of electronics establishments in Britain and France, this paper finds that the two samples of establishments were operating in distinctively different national labour markets for engineers and scientists, reflecting structural differences in national higher education systems and a far higher level of individual mobility between enterprises in Britain than is found in France. These differences were found to have very little effect on quantitative measures of establishments' external research interactions which tended to reflect other national-institutional differences such as continued government support for public laboratories in France of a kind which have now been largely privatised in Britain. However, qualitative evidence pointed to a faster rate of development of new external knowledge sourcing and relationship building in Britain which was partly stimulated by the greater mobility of individual engineers and scientists between enterprises and other organisations bringing new personal networks of external contacts with them. These tendencies contrasted with a marked stability in external research linkages in France. The paper suggests that the greater openness of British R&D networks to new ideas and knowledge may be particularly advantageous in fast-changing high-tech industries such as electronics.